Ubuntu Software (aka Gnome Software) on Ubuntu 18.04 has started giving the error message: Unable to get a list of updates: remote lvfs has no cache signature
This issue started recently and, based on a bit of online research, it may be related to Linux Vendor Firmware Service (LVFS) and the fwupd application.
Here are the installed fwupd packages:
~$ apt list --installed | grep fwupd
fwupd/bionic-updates,now 1.2.10-1ubuntu2~ubuntu18.04.3 amd64 [installed]
fwupd-signed/bionic-updates,now 1.10~ubuntu18.04.3+1.2.10-1ubuntu2~ubuntu18.04.3 amd64 [installed,automatic]
fwupdate/bionic-updates,now 12-7~ubuntu18.04.3 amd64 [installed]
fwupdate-signed/bionic-updates,now 12-7~ubuntu18.04.3 amd64 [installed]
libfwupd2/bionic-updates,now 1.2.10-1ubuntu2~ubuntu18.04.3 amd64 [installed,automatic]
and
~$ snap list | grep fwupd
fwupd 1.4.2 2084 latest/stable richard-hughes classic
